When dispersing liquids on transfer surfaces of gas/liquid contact reactors, e.g. of plate transfer reactors, the liquids are usually sprinkled or sprayed on using appropriate devices (sprinklers, nozzles, jets, droplet distributors, etc.)
Devices with open or closed trays or ducts in connection with overflows and/or liquid outlet openings are used as well.
For example, from DE-OS 43 21 743 a liquid distribution device is known, with which a liquid is dripped onto a non-woven fabric from a porous tube. Also known from this document is the use of spray distribution devices.
From DE 36 40 886 C1 a liquid distributor for mass and heat transfer columns is known, which consists of one main distribution device with parallel ducts in the form of trays, in which the sidewalls of the trays are perforated to release the liquid. In longitudinal direction along the outside of the walls of the channels, guiding metal fins are affixed, which on the one hand encompass the perforations with recesses from below and thus exercise a centering effect on the liquid This has a centering effect on the liquid flowing down the sidewalls of the trays while the guiding fins on the other hand have cut-outs that are downward offset to the recesses and which guide the liquid to dripping tongues lying in between.
With these conventional liquid distributors the risk of droplet formation arises and with that the associated risk of small droplets being carried out by the gas flow and consequently their discharge out of the reactor. Therefore these conventional liquid distributors require demisters downstream in the gas flow, which cause additional cost.
To distribute very small amounts of liquid so-called thin film evaporators or thin film absorbers are known, in which a mechanical wiper disperses a thin film of liquid onto a transfer surface. This design requires considerable effort with regard to construction, involves numerous moving parts and is therefore expensive, prone to malfunction and requires high maintenance.
Designs with open or closed trays or ducts in connection with overflows and/or outlet openings bear the risk of silting up and clogging, respectively. In the particular application as air dehumidifiers (absorbers) for air conditioning systems it was to this date not economically feasible, to disperse the physically required lowest possible mass flow of liquid (adsorbent, usually a concentrated salt solution), which is required for the absorption of water vapour from the air, in such a way onto the mass transfer surfaces of an appropriate reactor, that an extremely thin, yet continuous film of liquid could cause a significant concentration change in the liquid (sorbent).